Java Why Is public static void main(String[] args) Essential in Java Programs?

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The line "public static void main(String[] args)" is crucial in Java as it defines the entry point for program execution. The "main" method is where the program begins running. The "void" keyword indicates that this method does not return a value. The "public" access modifier allows the method to be accessible from anywhere, while "static" means it belongs to the class itself rather than an instance of the class. The "String[] args" parameter allows the program to accept command-line arguments, enabling users to influence how the program operates. For instance, in a class like "Circle," the main method could be used to draw a circle based on a color specified in the command line. Without the main method, a Java class cannot be executed, leading to a NoSuchMethodException. In contrast, applets do not require a main method, as execution starts with methods like init() or paint().
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As a very beginner to java a very basic question is in mind.in every java program we write the first line after mentioning the name of the class as

____________________________________

public static void main(String[] args)

_____________________________________

so i want to know the importance of this line and each component in this line because i am not getting to it.
i will be very thankful for urs help.
 
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Main is the function from which program execution stars.void implies that the function doesn't return a value.The rest you can put off until later.public(after learning classes)statis(types of variables)
 
Since you're beginning, you may not understand the significance of the "public static," but the String[] args may be useful to know. Those are some arugments to control how your program works.

Say you have a class "Circle." that looks something like this:

public class Circle
{

public static void main(String[] args)
{
drawCircle(args[0]);
}

void drawCircle(String a){...} //would contain code for drawing a circle of a certain color.

}

Upon calling your program, you'd need to tell the program what color you wanted. You would, for example, call "Circle blue," and it would draw a blue circle.
 
It is method main() that makes a Java class runnable. You cannot run other Java classes that don't contain this method. The compiler will give a NoSuchMethodException.
A different case is with applets, where you don't have to declare main(). Execution starts with method init(), if any, or with paint().
 
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